Validating primary subsets of received sensor data using computer cryptographic processing

ABSTRACT

A computer identifies capture device output that represents an aspect of a recorded event. The computer cryptographically processes the primary subsets of capture device output to produce a validatable master file which includes master file media data primary subset from the capture device output, master primary subset metadata of the master file media data primary subset, and master file blocktree data. The master file blocktree data includes a master file block history portion, a master file signature key portion, and a signed hash of the master file media data primary subset. The computer also modifies the master file media data primary subset to produce a reference file media data primary subset. reference files and distributable files. The computer verifies the authenticity of each of these files.

BACKGROUND

The present invention relates generally to the field of media capture,and more specifically, to verifying authenticity of originally-capturedmedia files.

Data may be obtained from sensors in a variety of capture devices, suchas a photographic cameras, audio capture devices, infrared video capturedevices, radar spatial information capture devices, sonar spatialinformation capture devices, lidar spatial information capture devices,laser “trip-wires,” chemical signature information capture devices,X-ray image capture devices, microwave image capture devices, barometricpressure reading capture devices, anemometer, etc. In some cases, isimportant to be able to verify that stored data captured by one or moreof these devices authentically represents what was captured by thedevice.

SUMMARY

Aspects of the present disclosure recognize and address the shortcomingsand problems associated with confirming the authenticity of primarysubsets of as-recorded media files. Other aspects of the invention allowprimary subsets of an original media file to be identified as importantdata subsets and allow the nature of changes made to those portions tobe validated. Other embodiments of the invention assess the veracity offiles supposedly based on changes made to verifiable, as-recorded mediafiles. It is noted that the as-recorded media files may includesecondary subsets, as well as primary subsets. By selecting certainaspects of media files to validate, aspects of the present inventionprovide customized file assessment, allowing end users to select ofportions (e.g., primary subsets, including foreground layers withinvisual and audio files, or other aspects selected by one skilled in thisfield) of media in which it is preferable to have on only minimal (orno) changes and portions, (e.g., secondary subsets, including backgroundlayers within visual and audio files, or other aspects selected by oneskilled in this field) of media in which relatively more changes will betolerated.

In an embodiment, a computer-implemented method includes: receiving, bya computer, a capture device output, the output representing an aspectof a recorded event. The computer cryptographically processes thecapture device output to produce a validatable master file, the masterfile including at least one primary subset. The validatable master fileincludes a master file media data primary subset from the capture deviceoutput, master metadata, and master file blocktree data; The master fileblocktree data includes a master file block history portion, a masterfile signature key portion, and a signed hash of the master file mediadata primary subset. According to aspects of the invention, thecryptographic processing includes dividing the media data, by thecomputer, into at least one tracked data subset corresponding to theprimary subset. The computer generates a hash of the at least onetracked data subset. The computer generates metadata of the hash of theat least one tracked data subset. The computer combines the hash and themetadata of the hash into at least one tracked data packet. The computercryptographically signs the at least one data packet. According toaspects of the invention, the computer modifies the master file mediadata primary subset to produce a reference file media data primarysubset. According to aspects of the invention the computer prepares areference file including the reference file media data primary subset,reference file metadata, and reference file blocktree data. Thereference file blocktree data includes the master file blocktree dataand blocktree incrementing information. The blocktree incrementinginformation includes a hash of the master file blocktree data, referencefile blocktree metadata, a signed hash of primary subset metadata, asigned hash of a change log incrementing the media data primary subsetfrom the master file media data primary subset, and a signed hash of thereference file media data primary subset. According to aspects of theinvention, the computer the reference file further includes instructionsindicating replicable changes made, by the computer, between themodified primary subset media and the master file media data primarysubset. According to aspects of the invention, the computer receives achallenged master file identified as a copy of the validatable masterfile. The computer receives a request to validate the challenged masterfile. The computer executes a master file validation routine to assessvalidity of the challenged master file. The master file validationroutine includes hashing, by the computer, media data primary subset ofthe challenged master file to generate a hashed challenged master filemedia data primary subset. The computer unsigns a signed hash portion ofthe media data primary subset of the challenged master file to generatean unsigned challenged master file media data primary subset. Thecomputer determines whether the hashed challenged master file media dataprimary subset and the unsigned challenged master file media dataprimary subset match. According to aspects of the invention, thecomputer receives receiving, by the computer, a reference fileidentified as a modified version of the master file. The computerreceives a request to determine whether the reference file is a modifiedversion of the master file. The computer executes a reference fileverification routine. The reference file verification routine includesdetermining, by the computer, whether the hash of the master fileblocktree data and a hash of blocktree data of the reference file match.The computer applies changes indicated by the blocktree incrementinginformation to a media data primary subset in the reference file togenerate a hashed reference file media data primary subset and unsigningreference file blocktree data to generate unsigned reference fileblocktree data. The computer determines whether the hashed referencefile media data primary subset and the unsigned reference file blocktreedata match. According to aspects of the invention, the computer receivesa reference file identified as an authentic modification of the masterfile. The computer receives a distributable file. The computer receivesa request to determine whether the distributable file is an authenticmodification of the reference file identified as an authenticmodification of the master file. The computer executes a distributablefile verification routine. The distributable file verification routineincludes determining whether a hash of distributable file blocktree datamatches a hash of the reference file blocktree data and whether a hashof a distributable file media data primary subset matches acorresponding unsigned hash of a representative media block.

In another embodiment of the invention, a system includes A computerprogram product comprising a computer readable storage medium havingprogram instructions embodied therewith, the program instructionsexecutable by a computer to cause the computer to: receive, using thecomputer, a capture device output, the output representing an aspect ofa recorded event; cryptographically process, using the computer, thecapture device output to produce a validatable master file, the masterfile including at least one primary subset; wherein the validatablemaster file includes a master file media data primary subset from thecapture device output, master metadata, and master file blocktree data;wherein the master file blocktree data includes a master file blockhistory portion, a master file signature key portion, and a signed hashof the master file media data primary subset.

In another embodiment of the invention, a computer program productcomprises computer readable storage medium having program instructionsembodied therewith, the program instructions executable by a computer tocause the computer to: receive a capture device output, the outputrepresenting an aspect of a recorded event; cryptographically processthe capture device output to produce a validatable master file; whereinthe validatable master file includes a media data primary subset fromthe capture device output, master primary subset metadata of the masterfile media data primary subset, and master file blocktree data; whereinthe master file blocktree data includes a master file block historyportion, a master file signature key portion, and a master file primarysubset signed data hash.

Some issues with confirming authenticity of data files includedifficulty in determining whether a given file in fact contains a truecopy of selected portions of the as-recorded data from a capture device.Other problems can include determining whether instructions in a changelog are true representations of changes that have occurred to primarysubsets of a file containing a modified version of captured data. Otherproblems occur when trying to validate the authenticity of portions ofvarious versions of files (e.g., reference files and distribution files)which are not duplicates of a master file but which, instead, supposedlycontain verifiable variations of primary subsets of the master file.

Aspects of the present invention enables a computer to replicate changesmade to an original media file to get resulting composite media files(e.g., with primary and secondary aspects) and validate whether selectedportions (e.g., primary and/or secondary aspects) of the resultingcomposite file are identical to representations of those aspects aspresent in a composite file whose integrity is being challenged.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, features and advantages of the presentinvention will become apparent from the following detailed descriptionof illustrative embodiments thereof, which is to be read in connectionwith the accompanying drawings. The various features of the drawings arenot to scale as the illustrations are for clarity in facilitating oneskilled in the art in understanding the invention in conjunction withthe detailed description. The drawings are set forth below.

FIG. 1 is a schematic block diagram illustrating an overview of a systemfor computer-implemented generation of a validatable master file mediadata primary subset.

FIG. 2 is a flowchart illustrating a method, implemented using thesystem shown in FIG. 1 , of capturing media data and storing anassociated master file.

FIG. 3 is an exemplary format of a master file having primary subsetsaccording to aspects of the invention.

FIG. 4 is a flowchart illustrating a method, implemented using thesystem shown in FIG. 1 , of modifying a master file to generate primarysubsets of a reference file according to aspects of the invention.

FIG. 5 is an exemplary format of a reference file having primary subsetsaccording to aspects of the invention.

FIG. 6 is a flowchart illustrating a method, implemented using thesystem shown in FIG. 1 , of validating a master file having primarysubsets according to aspects of the invention.

FIG. 7 is a flowchart illustrating a method, implemented using thesystem shown in FIG. 1 , of validating primary subsets of a referencefile according to aspects of the invention.

FIG. 8 is a flowchart illustrating a method, implemented using thesystem shown in FIG. 1 , of validating a primary subsets ofdistributable file according to aspects of the invention.

FIG. 9A is a schematic representation of an exemplary file containing aninternal blocktree according to aspects of the invention.

FIG. 9B is a schematic representation of aspects of an exemplary blockstructure according to aspects of the invention.

FIG. 10A is a schematic representation of aspects of an exemplary mediafile containing a blocktree in a media file according to aspects of theinvention.

FIG. 10B is a schematic representation of aspects of an exemplary mediafile containing a blocktree having a single branch of dependencies.

FIG. 10C is a schematic representation of aspects of an exemplary mediafile containing a blocktree having various dependencies.

FIG. 11 is a schematic block diagram depicting a computer systemaccording to an embodiment of the disclosure which may be incorporated,all or in part, in one or more computers or devices shown in FIG. 1 ,and cooperates with the systems and methods shown in FIG. 1 .

FIG. 12 depicts a cloud computing environment according to an embodimentof the present invention.

FIG. 13 depicts abstraction model layers according to an embodiment ofthe present invention.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of exemplaryembodiments of the invention as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the embodiments described hereincan be made without departing from the scope and spirit of theinvention. In addition, descriptions of well-known functions andconstructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used to enablea clear and consistent understanding of the invention. Accordingly, itshould be apparent to those skilled in the art that the followingdescription of exemplary embodiments of the present invention isprovided for illustration purpose only and not for the purpose oflimiting the invention as defined by the appended claims and theirequivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a participant” includes reference toone or more of such participants unless the context clearly dictatesotherwise.

Now with combined reference to the Figures generally and with particularreference to FIG. 1 and FIG. 2 , an overview of method 200 forconfirming the authenticity of primary subsets of as-recorded mediafiles, the nature of changes made to primary subsets of as-recordedmedia files, and the veracity of files supposedly based on theverifiable changes made to primary subsets of as-recorded media files.Method 200 is usable within a system 100 as carried out by a servercomputer 120 having optionally shared storage 122 and aspects 124(including a signal processing chip 126, a cryptographic processing chip128, ROM 130, and a general processing chip 132 that cooperativelyconfirm the authenticity of primary subsets of as-recorded media files,indicate the nature of changes made to primary subsets of as-recordedmedia files, and demonstrate the veracity of files supposedly based onthe verifiable changes made to primary subsets of as-recorded mediafiles. It is noted that the storage 122 could, within the spirit ofaspects of this invention, take a variety of forms, including areceiving bus, an I/O bus, a networking card, or other items capable ofreceiving file data such as a master file 300, or a reference file 500.

It is noted that the method of the current invention is expected to beused by participant groups (e.g., professional organizations, corporateentities, etc.), individuals, and computerized programs such asApplication Programming Interface (API) that have appropriate rights tocapture the data described herein, as well as the right to use andprocess the captured data in the ways described. It is also envisionedthat any models whose likeness is captured or used in accordance withaspects of the present invention have provided valid consent for suchcapture and use. The data described herein is captured and used inaccordance with legally-appropriate methods and with all consentnecessary for the intended uses.

According to aspects of the invention, a capture device with a sensor136 records an aspect of reality 134, such as an image, a sound, apressure reading, etc. and passes the aspect along to a signalprocessing chip 126 associated with a server computer 120. The capturedevice sensor sends raw data to the signal processing chip 126, wheresystem 100 converts the raw data into a format useable by the system 100and optionally compressed. If the signal processing chip 126 does notcompress the data, an optional compression chip (not shown) may be used.The cryptographic processing chip 128 takes the processed (and possiblycompressed) data, divides the data into predetermined subsets (such aspixels or other discrete units associated with the data beingprocessed), and hashes the subsets. According to aspects of theinvention, at least one of the subsets to be hashed corresponds with aprimary subset of the media data. It is noted that all or substantiallyall file subsets may be deemed primary subsets (e.g., as in scenariosfor which no (or only minimal) changes are tolerated). Using the hashesof the subsets (including the subsets corresponding to primary subsets),the cryptographic processing chip 128 adds primary subset metadata foreach hash (e.g., the subset, timestamp, etc.) and cryptographicallysigns the primary subset hash data packets (i.e., hashes with respectiveprimary subset metadata) with an immutable, unique private key held inthe ROM 130. The signed primary subset data hashes and media data arepassed to the general processing chip 132, which combines the signedprimary subset data hashes and media data, along with any relevantmetadata, into a master file 300 having the format shown in FIG. 3 .According to aspects of the invention, the master file blocktree data310 includes a master file block history portion 311A, a master filesignature key portion 314A, and a master file primary subset signed datahash 316A. It is noted that certain portions of the master file blockhistory may be null or include other agreed upon content reflecting theoriginal, non-changed nature of the master file 300. Aspects of thepresent invention enable tracked generation and distribution of mediawhere multiple portions (e.g., primary portions and secondary portions)of the media have different traceable histories that can be validated astruthful modifications from a copy of the original media file. Aspectsof the invention validate individual histories of various portions(e.g., different layers, etc.) of a media file as containing authentic,tolerable modifications (e.g., no changes allowed for primary subsets ofmedia data, while modifications to secondary subsets are tolerated orother arrangements selected in accordance with the judgment of oneskilled in this field) to an associated original media file.

With additional reference to FIG. 2 , the server computer 120, at block202 receives sensor data from capture device 136; the sensor data isconverted into media data (including a portion of media data which istracked) that is cryptographically processed in block 206. Withcontinued reference to FIG. 2 , the cryptographic processing includesdividing media data, at block 208, into subsets (with at least one ofthe subsets corresponding to the media data primary subset) and hashingthe subsets at block 211. It is noted that the identification of primarysubsets may be accomplished by an end user selection, by the servercomputer 120 in accordance with preferences established in acomputer-implemented selection algorithm, or in any other manner chosenby one of known skill in this art. At block 212, the cryptographicprocessing chip 128 combines the hashed media data primary subset withprimary subset metadata (which may, itself, be hashed) into hashedprimary subset data packets. At block 214, the cryptographic processingchip 128 cryptographically signs the primary subset hashed data packets.The general processing chip 132 generates a master file 300 at block216, and the server computer 120 stores the master file in sharedstorage 122 at block 218.

With reference to FIG. 3 , the format of a master file 300 according toaspects of this invention is shown; the format, according to embodimentsof this invention, includes three portions: metadata 301, sensor mediadata primary subset 302, and internal blocktree data 310. In particular,the master file 300 shown in FIG. 3 is a file with only one block ofblocktree data 311A, and this single block is known as a genesis block.The file format may be implemented as an extension to existing fileformats. It is noted that while FIG. 3 shows master file 300, the system100 generates other files (known as reference files 500, which are shownschematically in FIG. 1 and in more detail in FIG. 5 ) when modifying amaster file 300 according to aspects of this invention, reference fileshave the same overall format (as shown in FIG. 5 , discussed in moredetail below).

The internal blocktree data 310 includes blocks of information about thefile and versions of its media data (and optionally, metadata) held inblocks that are cryptographically linked by including the cryptographichash of the previous block, which corresponds to a previous version ofthe primary subset data (and optionally, primary subset metadata) of themaster file 300 and a reference file 500.

It is noted that the media data primary subset 302 of the master file300 represents original media data captured by a sensor in capturedevice 136, and the blocktree data 310, according to aspects of thisinvention, is a non-distributed blocktree (i.e., a data structure whereeach data block contains the cryptographic hash of the previous block)that is internal to a master file 300.

The blocktree data 310 contains a hashable portion and optionally(depending on the file variant) certain extensions that are not includedin the block hash. The hashable portion includes the previous block hash313A, 513B, etc. (or, for the genesis block, some agreed upon choice,such as null), the public key used in signatures for this block(optionally, any metadata about the public key), a hash (or root hash)of the changes made from the previous data version to get to thisversion (or, in the case of the genesis block, some agreed upon choice,such as null), and a signed hash of the current media data primarysubset 302 in one of two formats. The first signed hash format includesa signed hash of the file metadata for this version (or its hash) andthe file media data primary subset for this version (or its hash/roothash); the second signed hash format includes a signed hash of the filemedia data primary subset for this version, and (optionally) a signedhash of the file metadata for this version. It is noted that the masterfile 300 (a file with an internal blocktree that only has one block) hasblocktree data divided into subsections as follows: general filemetadata 301, media data (original from sensor) primary subset 302,internal blocktree data (for only one block) 310, the origin/genesisblock 311A, hashable portion 312A of the origin/genesis block, previousblock hash (in this case, null or some other predefined convention)313A, public key used in digital signatures optionally includingmetadata about the public key 314A, other block metadata 315A, either(a) signed hash of the file metadata (or its hash) and the file mediadata primary subset (or its hash/root hash); or (b) signed hash of thefile metadata and a signed hash of file (or root hash) of the file mediadata primary subset 316A. The master file 300 also includes signedhashes 317A of primary subsets metadata 322A. The master file 300, atblock 318A contains signed hashes of prescriptive instructions containedin change logs 320A. It is noted that for the master file 300, block318A may be null or some other value agreed to represent the nature ofthe master file as unchanged.

In addition to the structure described above, there are three optionalfile extension portions 320A, 321A, & 322A included in block 319A thatmay be included within aspects of this invention. The first extension isa change log 320A of some format that enables replicating the changes onthe previous version of the media data primary subset to get to thecurrent version of the media data primary subset. The change log 320includes information iteratively documenting the changes made occurringto the media data 302. For each iteration beyond the master file 300,the change log 320 includes associated information which representschanges to the media data 302 in that iteration. It is noted that forthe master file 300 itself, the change log 320 will preferably hold anull set value. The change log is only required for reference media filecopies. The change log is optional, but not necessary for distributablecopies. The second extension 321A is a copy of the media data primarysubset at that stage of the history of the media file. It is notrequired for any of the file variants, and simply may be value added.The third extension 322A is primary subset metadata that indicates whichportions of the media data are the primary subsets.

With reference to FIG. 4 , a method 400 to create a modified version 500(also known as a reference file) of the master file 300 is shown. Asnoted above, a reference file 500 according to aspects of this inventionis a modified version of the original, master file 300 generatedaccording to the flow logic shown in FIG. 4 . At block 404, the servercomputer 120 receives a copy of the master file 300 (including primarysubsets of the master file data), and at block 406, the server computer120 modifies the master file media data 302 using, for example, an imageor sound editing algorithm (not shown). After modifying the master mediadata 302, the server computer 120 receives, at block 408, a filecontaining the metadata 501, altered master media data primary subset502 (as seen in FIG. 5 and described in detail below).

More particularly, the server computer 120 saves the altered media data,at block 410, as reference file media data primary subset 502. Theserver computer 120, at block 412, generates reference file metadata501; at block 414, the server computer 120 combines reference file mediadata primary subset 502, reference file metadata 501, and reference fileblocktree data 510 into a reference file data packet. As used herein,the term blocktree refers to a traditional blocktree, a hashchain,cryptographically linked list, or other immutable data structure thatreplicates the functionality and data integrity that a blocktreeprovides. At block 416, server computer 120 cryptographically signs thereference file data packets. At block 418, the server computer 120generates reference file blocktree data 510 and updates the blocktree byadding the currently-iterated reference blocktree data 302 x to theexisting blocktree. At block 420, the server computer 120 generates areference file 500 containing the signed data packets 516 and saves thereference file blocktree data 510 at block 422.

As shown with reference to FIG. 5 , the reference file blocktree data510 contains information about the file and versions of its data (andoptionally, metadata) held in blocks that are cryptographically linkedby including the cryptographic hash of the previous block, whichcorresponds to a previous version of the data (and optionally, metadata)of the file. Additional detail about a preferred structure for thereference file according to aspects of the invention is now providedwith particular reference to FIG. 5 . A reference file with an internalblocktree that has multiple blocks is shown at 500; this file representsprimary subsets of media that has been modified since its originalcreation. The reference file includes general reference file metadata501, reference file media data (modified from original) primary subset502, and internal blocktree data 510. The internal blocktree data 510includes a series of blocks, including 511A (the genesis blockassociated with the master file 300), 511B (the modified blockassociated with the first reference file (i.e., a first round of changesto the master file 300)), and 511 x (a second or later reference blockassociated with possibly several rounds of changes to the originalmaster file 300). Each block in the chain is further divided asdescribed above into subsections, and the subsections are labelled asaccording to a numerical series (i.e., 511, 512, 513, 514, 515, 516,517, 518, 519, 520, 521, and 522). As each round of media data changestake place, the server computer 120 generates a new reference file 500and associated blocktree data, with each block in the chain maintainingthe same relative format. For convenience, numerical references amongthe reference file blocktree subsections follow the same numericalarrangement (e.g., 511, 512, 513, 514, 515, 516, 517, 518, 519, 520,521, and 522), with each generation of subsections having an indexedletter suffix (starting at “B”) appended thereto. This is schematicallyshown in FIG. 5 as 511B, 512B, 513B, 514B, 515B, 516B, 517B, 518B, 519B,520B, 521B, and 522B and 511 x, 512 x, 513 x, 514 x, 515 x, 516 x, 517x, 518 x, 519 x, 520 x, 521 x, and 522 x. If more than twenty-sixgenerations of changes occur, (e.g., at the end of a run through thealphabet), an additional suffix letter, starting with A is added (e.g.,a second run through the alphabet would begin with BA, BB, and so on).It is noted that suffix letter “A” is reserved for data associated withthe original, master file 300 and used to identify the genesis/originblock generated for the master file.

With continued reference to FIG. 5 , the reference blocktree data 510also contains a hashable portion 512 x which includes the previous blockhash 513 x, a public key 514 x, and other block metadata 515 x, with anyrelevant metadata, and either option version of the signed, hashed mediadata described above. The public key 514 x represents the algorithmmaking the modifications, as either the public key corresponding to ageneric private key shared by all algorithms of the same version or apublic key corresponding to a private key that is unique to thatalgorithm installation.

The server computer 120 attaches three extensions to the blocktree data510 x. The first extension, 520 x, is a change log of some format thatenables replicating the changes on the previous version of the mediadata primary subset to get to the current version of the media dataprimary subset. As noted above, the change log 520 x includesinformation iteratively documenting the changes made occurring to thereference file media data primary subset 502. For each iteration beyondthe master file 500, the change log 520 x includes associatedinformation which represents changes to the reference file media dataprimary subset 502 in that iteration. The change log 520 x is onlyrequired for reference media file copies. The change log 520 x isoptional, but not necessary for distributable copies. The secondextension, 522 x, is primary subset metadata which describes whatsubsets of the reference file media data primary subset 502 areconsidered important and for which changes are to be tracked. The thirdextension, 521 x, is a copy of the reference file media data primarysubset 502 (or only the media data primary subset) at that stage of thehistory of the media file. It is not required for any of the filevariants, and simply may be value added.

The blocktree also includes a hashable portion of the block 512 x, aprevious block hash (in the case of block A, the genesis block, thisvalue is null or some other predefined convention) 513 x, a public keyused in digital signature, that may include metadata about the publickey 514 x, and other block metadata 515 x. Block 516 x includes asigned, hash of media data primary subset and possibly metadata. Thereare two preferred formats for this information: (a) signed hash of thefile metadata (or its root hash) and the file media data primary subset(or its hash/root hash), or (b) signed hash of the file metadata and asigned hash (or root hash) of the file media data primary subset. Otherformats for this signed, hashed information may also be selectedaccording to the preferences of one skilled in this art. Block 517 xcontains a signed hash of primary subset metadata, and block 518 x is asigned hash (or signed root hash) of block incrementing instructions 520x. It is noted that instructions and the associated hash may only bepresent as a null value in block A, the genesis block, as no changesfrom the master file will have occurred. Block 519 x is a “blockextension”, and this is information held in reference media files whichis not required in (but not restricted from) distributable media files,and it is preferably not included in the block hash. Block 520 xcontains prescriptive, replicable instructions detailing how to get fromthe version of the media data represented by the previous block to theversion of the media data represented by this block (present as a nullin block A because, as noted elsewhere, block A represents the original,master file version of the media that came from the sensor of thecapture device 136). Block 521 x contains an optional, redundant copy ofmedia data (or only the media data primary subset) at this point in thehistory of the media, and 522 x contains primary subset metadata whichdescribes what subsets of the media data are considered important andfor which changes are to be tracked.

With reference to FIG. 6 , a process for validating a master file 300according to aspects of the present invention will now be described. Atblock 604, the server computer 120 receives a challenged master file(hereafter, “CMF”) which is to be validated. At block 606, the servercomputer 120 hashes CMF primary subset data and CMF primary subsetmetadata to generate first CMF comparison elements including unsignedhashes of CMF media data primary subset and CMF primary subset metadata.At block 608, the server computer 120 unsigns the signed hash of the CMFmedia data primary subset and signed CMF primary subset metadata fromthe CMF master blocktree data to generate second CMF comparison elementsincluding unsigned signed hash of the CMF media data primary subset andsigned CMF primary subset metadata. At block 610, the server computer120 compares the first CMF comparison elements to the second CMFcomparison elements and determines at block 612 whether those filesmatch. If the first CMF comparison elements and second CMF comparisonelements match, then the server computer 120 deems the CMF at block 614to be an authentic copy of the original reference file 300. However, ifthe first CMF comparison elements and second CMF comparison elements donot match, the server computer 120 does not confirm the authenticity ofthe CMF, and the server computer deems the CMF to be inauthentic atblock 616.

It is noted that according to aspects of the present invention, anassumption is made that the public key of the origin block is valid(i.e., representing of the sensor device that supplied it), and thecapture device 130 that supplied the public key is trusted (thisincludes that the sensor of the capture device 136 has not been tamperedwith since the public key was embedded into the master media file).Verifying that sensor of the capture device 136 is trusted may be donein a variety of ways that may or may not involve the applicationvalidating the original media file.

With reference to FIG. 7 , a process 700 for validating a reference file500 according to aspects of the present invention will now be described.At block 704, the server computer 120 receives a reference file 500which is to be compared with a master file 300 for authentication (e.g.,whether the reference file content represents content that has beenmodified from the master file content in accordance with instructionsprovided with reference file). At block 706, the server computer 120compare reference file 500 genesis block hashes to master file 300genesis block hashes, and at block 708, the server computer determineswhether the compared genesis block hashes match. If the compared genesisblock hashes do not match, the reference file may not be authentic, andthe computer moves to block 718.

If the compared genesis block hashes do match, then the computer movesto block 710 and applies changes provided in reference file blocktreeincrementing information to master file media data primary subset andhashes the results to generate first reference file comparison elements.At block 712, the server computer 120 unsigns the signed hashes in RFblocktree data to generate second RF comparison elements. It is notedthat the first reference file comparison elements include hashedreference file media data primary subset or other elements selected inaccordance with judgement used by one skilled in the art. It is notedthat the second reference file includes unsigned reference fileblocktree data or other elements selected in accordance with judgementused by one skilled in the art. At block 714, the server computer 120determines whether the first reference file comparison elements andsecond reference file comparison elements match. If the reference filecomparison elements match, the server computer 120 moves to block 716and verifies the authenticity of the reference file 300. If thereference file comparison elements do not match, the validity of thereference file is not confirmed, and the computer moves to block 718, inwhich the computer does not verify the authenticity of the referencefile 300, and the reference file may be labeled as inauthentic.

Now with reference to FIG. 8 , a method of validating a distributablefile according aspects of this invention will now be described. At block804, the compute receives a distributable file (hereafter, “DF”) and averified authentic reference file (hereafter, “VARF”) to determinewhether the DF, which is claimed to be an authentic derivative or othermodification of the VARF, is actually a file containing an authenticversion of media data contained in the VARF. At block 806, the computercompares hashes of DF blocktree data to hashes of VARF blocktree data,and at block 808 determines whether the compared hashes of blocktreedata match. It is noted that the DF follows the same file format as theVARF without requirement for containing blocks 519 x and blocks includedtherein. If the compared hashes of blocktree data do not match, thedistributable file may not be authentic, and the server computer 120moves to block 816.

If the compared hashes of blocktree data do match, then the computermoves to block 810 and compares at block 812 the hash of the DF primarysubset media file to a corresponding unsigned hash of a representativemedia block. In one in embodiment, the corresponding unsigned hash isthe unsigned signed hash 516 x in the representative media block x, andthe representative media block x is the block that represents the mediadata primary subset in block 502 at the associated iteration in theblocktree history. If the hashes of the DF primary subset media file andthe hash in last DF blocktree block match, then the DF is deemed to beauthentic. At block 814, the computer verifies the authenticity of theDF.

Now with reference to FIG. 9A, an exemplary file 900 with an internalblocktree structure will be described. According to aspects of theinvention, the file 900 contains general file metadata portion 902, amedia data portion 904, and an internal blocktree 906. In an embodiment,the blocktree 906 is an arrangement of data blocks in which each datablock contains the cryptographic hash of at least one previous blockfrom one or more prior branches. According to aspects of the invention,the blocktree 906 is an internal (e.g., stored locally) blocktreelocated within the exemplary file 900.

Now with reference to FIG. 9B, aspects of an exemplary block structure908 will be described. The block structure 908 includes hashable portionof the block 910. The hashable portion of the block 910 includesprevious block hash(es) 912 which, according to aspects of theinvention, may be a null or some other predefined convention for anoriginal media file. According to aspects of the invention, the previousblock hash 912 may be a single block hash if there is only one immediatepredecessor for current block. According to aspects of the invention,when multiple immediate predecessors exist, the previous block hash 912includes the hash of each immediate predecessor block. The hashableportion of the block 910 includes public key 914 used in digitalsignatures which, according to aspects of the invention; may includemetadata about the public key. The hashable portion of the block 910includes other block metadata 916, signed hashes of the importantsubsets of the media data and optionally metadata 918, and signed hashof the important subsets metadata 920. The hashable portion of the block910 includes a signed hash (possibly root hash) of instruction block 930which, according to aspects of the invention, may be a null or someother predefined convention in an origin block, as no changes haveoccurred. The block structure 908 includes block extension 924.According to aspects of the invention, block extension 924 is present inreference media files, is not required in (but not restricted from)distributable media files, and is not typically included in the blockhash. In an embodiment the block extension 924 includes a copy of themedia data (or subsets of it) at this point in the history (e.g., asmeasured by change iterations) of the media. According to aspects of theinvention, the block extension 924 includes important (e.g., primary)subsets metadata 928 and a box of prescriptive, replicable instructions930 detailing changes made between the version of the media datarepresented by the previous block(s) and the version of the media datarepresented by the current block.

Now with reference to FIG. 10A, aspects of an exemplary blocktree 1002structure will be described. In an embodiment, the blocktree 1002 is anoriginal media file containing one (e.g., genesis) block 0x79b4.

Now with reference to FIG. 10B, aspects of an exemplary blocktree 1004structure with a single branch of dependencies will be described.According to aspects of the invention, the blocktree 1004 representsmedia blocks 0x8bb2, 0x0b78, 0x12d8, 0xfe95 representing a singlehistory.

Now with reference to FIG. 10B, aspects of an exemplary blocktree 1006with various forms of dependencies, in which arrows point to theimmediate block dependencies. According to aspects of the invention, theblocktree includes three origin blocks 0xfd45, 0x48f3, 0x5535. In anembodiment, block 0x2135 has a single one immediate dependency 0xfd45.In an embodiment, 0xaa4b has three immediate dependencies 0x2135,0x48f3, 0x5535. In an embodiment, 0x0b0b0 has two immediatedependencies. According to aspects of the invention, including a lineardescendent (not shown) of 0xaa4b, and 0x5535. It is noted that although0xaa4b also has 0x5535 as an immediate dependency, 0x0b0b0 could alsohave 0x5535 as an immediate dependency. For ease of reference, thereference “0x” as used herein is a schematic representation of blocks inwhich that reference is found.

It is noted that the term capture device output as used herein includessensor data. It is also noted that the term master file as used hereinincludes a media file following the format shown in FIG. 3 and which isthe direct result of a capture device sensor recording reality throughthe previously described methods.

The term reference file as used herein includes a media file that is notintended for distribution and which uses a file format shown in FIG. 5 .This format may include change logs of varying formats or no changelogs. A reference media file is distinct from a master media filebecause it has undergone alterations according to the previouslydescribed methods.

The term distributable media file includes a media file that is intendedfor distribution to end recipients. Distributable media files use aformat shown on FIG. 5 . It is noted that a distributable media file inwhich the media data has not undergone any changes (and thus, theblocktree only contains the genesis block) is substantially the same asa master media file. It is also noted that if metadata about the file isnot considered to be essential (and thus its hashes are not included inthe blocktree), metadata in a distributable media file may vary fromthat in an original media file. The term change log includes replicableinstructions on how to modify a previous version of media data into thecurrent version of the media data (including, for example, how toincrement the media data primary subset from the master file media dataprimary subset).

Regarding the flowcharts and block diagrams, the flowchart and blockdiagrams in the Figures of the present disclosure illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the blocks may occur out of theorder noted in the Figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

Referring to FIG. 13 , a system or computer environment 1000 includes acomputer diagram 1010 shown in the form of a generic computing device.The method 100, for example, may be embodied in a program 1060,including program instructions, embodied on a computer readable storagedevice, or computer readable storage medium, for example, generallyreferred to as memory 1030 and more specifically, computer readablestorage medium 1050. Such memory and/or computer readable storage mediaincludes non-volatile memory or non-volatile storage. For example,memory 1030 can include storage media 1034 such as RAM (Random AccessMemory) or ROM (Read Only Memory), and cache memory 1038. The program1060 is executable by the processor 1020 of the computer system 1010 (toexecute program steps, code, or program code). Additional data storagemay also be embodied as a database 1110 which includes data 1114. Thecomputer system 1010 and the program 1060 are generic representations ofa computer and program that may be local to a user, or provided as aremote service (for example, as a cloud based service), and may beprovided in further examples, using a website accessible using thecommunications network 1200 (e.g., interacting with a network, theInternet, or cloud services). It is understood that the computer system1010 also generically represents herein a computer device or a computerincluded in a device, such as a laptop or desktop computer, etc., or oneor more servers, alone or as part of a datacenter. The computer systemcan include a network adapter/interface 1026, and an input/output (I/O)interface(s) 1022. The I/O interface 1022 allows for input and output ofdata with an external device 1074 that may be connected to the computersystem. The network adapter/interface 1026 may provide communicationsbetween the computer system a network generically shown as thecommunications network 1200.

The computer 1010 may be described in the general context of computersystem-executable instructions, such as program modules, being executedby a computer system. Generally, program modules may include routines,programs, objects, components, logic, data structures, and so on thatperform particular tasks or implement particular abstract data types.The method steps and system components and techniques may be embodied inmodules of the program 1060 for performing the tasks of each of thesteps of the method and system. The modules are generically representedin the figure as program modules 1064. The program 1060 and programmodules 1064 can execute specific steps, routines, sub-routines,instructions or code, of the program.

The method of the present disclosure can be run locally on a device suchas a mobile device, or can be run a service, for instance, on the server1100 which may be remote and can be accessed using the communicationsnetwork 1200. The program or executable instructions may also be offeredas a service by a provider. The computer 1010 may be practiced in adistributed cloud computing environment where tasks are performed byremote processing devices that are linked through a communicationsnetwork 1200. In a distributed cloud computing environment, programmodules may be located in both local and remote computer system storagemedia including memory storage devices.

The computer 1010 can include a variety of computer readable media. Suchmedia may be any available media that is accessible by the computer 1010(e.g., computer system, or server), and can include both volatile andnon-volatile media, as well as, removable and non-removable media.Computer memory 1030 can include additional computer readable media inthe form of volatile memory, such as random access memory (RAM) 1034,and/or cache memory 1038. The computer 1010 may further include otherremovable/non-removable, volatile/non-volatile computer storage media,in one example, portable computer readable storage media 1072. In oneembodiment, the computer readable storage medium 1050 can be providedfor reading from and writing to a non-removable, non-volatile magneticmedia. The computer readable storage medium 1050 can be embodied, forexample, as a hard drive. Additional memory and data storage can beprovided, for example, as the storage system 1110 (e.g., a database) forstoring data 1114 and communicating with the processing unit 1020. Thedatabase can be stored on or be part of a server 1100. Although notshown, a magnetic disk drive for reading from and writing to aremovable, non-volatile magnetic disk (e.g., a “floppy disk”), and anoptical disk drive for reading from or writing to a removable,non-volatile optical disk such as a CD-ROM, DVD-ROM or other opticalmedia can be provided. In such instances, each can be connected to bus1014 by one or more data media interfaces. As will be further depictedand described below, memory 1030 may include at least one programproduct which can include one or more program modules that areconfigured to carry out the functions of embodiments of the presentinvention.

The method(s) described in the present disclosure, for example, may beembodied in one or more computer programs, generically referred to as aprogram 1060 and can be stored in memory 1030 in the computer readablestorage medium 1050. The program 1060 can include program modules 1064.The program modules 1064 can generally carry out functions and/ormethodologies of embodiments of the invention as described herein. Theone or more programs 1060 are stored in memory 1030 and are executableby the processing unit 1020. By way of example, the memory 1030 maystore an operating system 1052, one or more application programs 1054,other program modules, and program data on the computer readable storagemedium 1050. It is understood that the program 1060, and the operatingsystem 1052 and the application program(s) 1054 stored on the computerreadable storage medium 1050 are similarly executable by the processingunit 1020. It is also understood that the application 1054 andprogram(s) 1060 are shown generically, and can include all of, or bepart of, one or more applications and program discussed in the presentdisclosure, or vice versa, that is, the application 1054 and program1060 can be all or part of one or more applications or programs whichare discussed in the present disclosure. It is also understood that thecontrol system 70 (shown in FIG. 8 ) can include all or part of thecomputer system 1010 and its components, and/or the control system cancommunicate with all or part of the computer system 1010 and itscomponents as a remote computer system, to achieve the control systemfunctions described in the present disclosure. It is also understoodthat the one or more communication devices 110 shown in FIG. 1 similarlycan include all or part of the computer system 1010 and its components,and/or the communication devices can communicate with all or part of thecomputer system 1010 and its components as a remote computer system, toachieve the computer functions described in the present disclosure.

One or more programs can be stored in one or more computer readablestorage media such that a program is embodied and/or encoded in acomputer readable storage medium. In one example, the stored program caninclude program instructions for execution by a processor, or a computersystem having a processor, to perform a method or cause the computersystem to perform one or more functions.

The computer 1010 may also communicate with one or more external devices1074 such as a keyboard, a pointing device, a display 1080, etc.; one ormore devices that enable a user to interact with the computer 1010;and/or any devices (e.g., network card, modem, etc.) that enables thecomputer 1010 to communicate with one or more other computing devices.Such communication can occur via the Input/Output (I/O) interfaces 1022.Still yet, the computer 1010 can communicate with one or more networks1200 such as a local area network (LAN), a general wide area network(WAN), and/or a public network (e.g., the Internet) via networkadapter/interface 1026. As depicted, network adapter 1026 communicateswith the other components of the computer 1010 via bus 1014. It shouldbe understood that although not shown, other hardware and/or softwarecomponents could be used in conjunction with the computer 1010.Examples, include, but are not limited to: microcode, device drivers1024, redundant processing units, external disk drive arrays, RAIDsystems, tape drives, and data archival storage systems, etc.

It is understood that a computer or a program running on the computer1010 may communicate with a server, embodied as the server 1100, via oneor more communications networks, embodied as the communications network1200. The communications network 1200 may include transmission media andnetwork links which include, for example, wireless, wired, or opticalfiber, and routers, firewalls, switches, and gateway computers. Thecommunications network may include connections, such as wire, wirelesscommunication links, or fiber optic cables. A communications network mayrepresent a worldwide collection of networks and gateways, such as theInternet, that use various protocols to communicate with one another,such as Lightweight Directory Access Protocol (LDAP), Transport ControlProtocol/Internet Protocol (TCP/IP), Hypertext Transport Protocol(HTTP), Wireless Application Protocol (WAP), etc. A network may alsoinclude a number of different types of networks, such as, for example,an intranet, a local area network (LAN), or a wide area network (WAN).

In one example, a computer can use a network which may access a websiteon the Web (World Wide Web) using the Internet. In one embodiment, acomputer 1010, including a mobile device, can use a communicationssystem or network 1200 which can include the Internet, or a publicswitched telephone network (PSTN) for example, a cellular network. ThePSTN may include telephone lines, fiber optic cables, transmissionlinks, cellular networks, and communications satellites. The Internetmay facilitate numerous searching and texting techniques, for example,using a cell phone or laptop computer to send queries to search enginesvia text messages (SMS), Multimedia Messaging Service (MMS) (related toSMS), email, or a web browser. The search engine can retrieve searchresults, that is, links to websites, documents, or other downloadabledata that correspond to the query, and similarly, provide the searchresults to the user via the device as, for example, a web page of searchresults.

The present invention may be a system, a method, and/or a computerprogram product at any possible technical detail level of integration.The computer program product may include a computer readable storagemedium (or media) having computer readable program instructions thereonfor causing a processor to carry out aspects of the present invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, configuration data for integrated circuitry, oreither source code or object code written in any combination of one ormore programming languages, including an object oriented programminglanguage such as Smalltalk, C++, or the like, and procedural programminglanguages, such as the “C” programming language or similar programminglanguages. The computer readable program instructions may executeentirely on the user's computer, partly on the user's computer, as astand-alone software package, partly on the user's computer and partlyon a remote computer or entirely on the remote computer or server. Inthe latter scenario, the remote computer may be connected to the user'scomputer through any type of network, including a local area network(LAN) or a wide area network (WAN), or the connection may be made to anexternal computer (for example, through the Internet using an InternetService Provider). In some embodiments, electronic circuitry including,for example, programmable logic circuitry, field-programmable gatearrays (FPGA), or programmable logic arrays (PLA) may execute thecomputer readable program instructions by utilizing state information ofthe computer readable program instructions to personalize the electroniccircuitry, in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a computer, or other programmable data processing apparatusto produce a machine, such that the instructions, which execute via theprocessor of the computer or other programmable data processingapparatus, create means for implementing the functions/acts specified inthe flowchart and/or block diagram block or blocks. These computerreadable program instructions may also be stored in a computer readablestorage medium that can direct a computer, a programmable dataprocessing apparatus, and/or other devices to function in a particularmanner, such that the computer readable storage medium havinginstructions stored therein comprises an article of manufactureincluding instructions which implement aspects of the function/actspecified in the flowchart and/or block diagram block or blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the blocks may occur out of theorder noted in the Figures. For example, two blocks shown in successionmay, in fact, be accomplished as one step, executed concurrently,substantially concurrently, in a partially or wholly temporallyoverlapping manner, or the blocks may sometimes be executed in thereverse order, depending upon the functionality involved. It will alsobe noted that each block of the block diagrams and/or flowchartillustration, and combinations of blocks in the block diagrams and/orflowchart illustration, can be implemented by special purposehardware-based systems that perform the specified functions or acts orcarry out combinations of special purpose hardware and computerinstructions.

It is to be understood that although this disclosure includes a detaileddescription on cloud computing, implementation of the teachings recitedherein are not limited to a cloud computing environment. Rather,embodiments of the present invention are capable of being implemented inconjunction with any other type of computing environment now known orlater developed.

Cloud computing is a model of service delivery for enabling convenient,on-demand network access to a shared pool of configurable computingresources (e.g., networks, network bandwidth, servers, processing,memory, storage, applications, virtual machines, and services) that canbe rapidly provisioned and released with minimal management effort orinteraction with a provider of the service. This cloud model may includeat least five characteristics, at least three service models, and atleast four deployment models.

Characteristics are as follows:

On-demand self-service: a cloud consumer can unilaterally provisioncomputing capabilities, such as server time and network storage, asneeded automatically without requiring human interaction with theservice's provider.

Broad network access: capabilities are available over a network andaccessed through standard mechanisms that promote use by heterogeneousthin or thick client platforms (e.g., mobile phones, laptops, and PDAs).

Resource pooling: the provider's computing resources are pooled to servemultiple consumers using a multi-tenant model, with different physicaland virtual resources dynamically assigned and reassigned according todemand. There is a sense of location independence in that the consumergenerally has no control or knowledge over the exact location of theprovided resources but may be able to specify location at a higher levelof abstraction (e.g., country, state, or datacenter).

Rapid elasticity: capabilities can be rapidly and elasticallyprovisioned, in some cases automatically, to quickly scale out andrapidly released to quickly scale in. To the consumer, the capabilitiesavailable for provisioning often appear to be unlimited and can bepurchased in any quantity at any time.

Measured service: cloud systems automatically control and optimizeresource use by leveraging a metering capability at some level ofabstraction appropriate to the type of service (e.g., storage,processing, bandwidth, and active user accounts). Resource usage can bemonitored, controlled, and reported, providing transparency for both theprovider and consumer of the utilized service.

Service Models are as follows:

Software as a Service (SaaS): the capability provided to the consumer isto use the provider's applications running on a cloud infrastructure.The applications are accessible from various client devices through athin client interface such as a web browser (e.g., web-based email). Theconsumer does not manage or control the underlying cloud infrastructureincluding network, servers, operating systems, storage, or evenindividual application capabilities, with the possible exception oflimited user-specific application configuration settings.

Platform as a Service (PaaS): the capability provided to the consumer isto deploy onto the cloud infrastructure consumer-created or acquiredapplications created using programming languages and tools supported bythe provider. The consumer does not manage or control the underlyingcloud infrastructure including networks, servers, operating systems, orstorage, but has control over the deployed applications and possiblyapplication hosting environment configurations.

Infrastructure as a Service (IaaS): the capability provided to theconsumer is to provision processing, storage, networks, and otherfundamental computing resources where the consumer is able to deploy andrun arbitrary software, which can include operating systems andapplications. The consumer does not manage or control the underlyingcloud infrastructure but has control over operating systems, storage,deployed applications, and possibly limited control of select networkingcomponents (e.g., host firewalls).

Deployment Models are as follows:

Private cloud: the cloud infrastructure is operated solely for anorganization. It may be managed by the organization or a third party andmay exist on-premises or off-premises.

Community cloud: the cloud infrastructure is shared by severalorganizations and supports a specific community that has shared concerns(e.g., mission, security requirements, policy, and complianceconsiderations). It may be managed by the organizations or a third partyand may exist on-premises or off-premises.

Public cloud: the cloud infrastructure is made available to the generalpublic or a large industry group and is owned by an organization sellingcloud services.

Hybrid cloud: the cloud infrastructure is a composition of two or moreclouds (private, community, or public) that remain unique entities butare bound together by standardized or proprietary technology thatenables data and application portability (e.g., cloud bursting forload-balancing between clouds).

A cloud computing environment is service oriented with a focus onstatelessness, low coupling, modularity, and semantic interoperability.At the heart of cloud computing is an infrastructure that includes anetwork of interconnected nodes.

Referring now to FIG. 12 , illustrative cloud computing environment 2050is depicted. As shown, cloud computing environment 2050 includes one ormore cloud computing nodes 2010 with which local computing devices usedby cloud consumers, such as, for example, personal digital assistant(PDA) or cellular telephone 2054A, desktop computer 2054B, laptopcomputer 2054C, and/or automobile computer system 2054N may communicate.Nodes 2010 may communicate with one another. They may be grouped (notshown) physically or virtually, in one or more networks, such asPrivate, Community, Public, or Hybrid clouds as described hereinabove,or a combination thereof. This allows cloud computing environment 2050to offer infrastructure, platforms and/or software as services for whicha cloud consumer does not need to maintain resources on a localcomputing device. It is understood that the types of computing devices2054A-N shown in FIG. 12 are intended to be illustrative only and thatcomputing nodes 2010 and cloud computing environment 2050 cancommunicate with any type of computerized device over any type ofnetwork and/or network addressable connection (e.g., using a webbrowser).

Referring now to FIG. 13 , a set of functional abstraction layersprovided by cloud computing environment 2050 (FIG. 12 ) is shown. Itshould be understood in advance that the components, layers, andfunctions shown in FIG. 13 are intended to be illustrative only andembodiments of the invention are not limited thereto. As depicted, thefollowing layers and corresponding functions are provided:

Hardware and software layer 2060 includes hardware and softwarecomponents. Examples of hardware components include: mainframes 2061;RISC (Reduced Instruction Set Computer) architecture based servers 2062;servers 2063; blade servers 2064; storage devices 2065; and networks andnetworking components 2066. In some embodiments, software componentsinclude network application server software 2067 and database software2068.

Virtualization layer 2070 provides an abstraction layer from which thefollowing examples of virtual entities may be provided: virtual servers2071; virtual storage 2072; virtual networks 2073, including virtualprivate networks; virtual applications and operating systems 2074; andvirtual clients 2075.

In one example, management layer 2080 may provide the functionsdescribed below. Resource provisioning 2081 provides dynamic procurementof computing resources and other resources that are utilized to performtasks within the cloud computing environment. Metering and Pricing 2082provide cost tracking as resources are utilized within the cloudcomputing environment, and billing or invoicing for consumption of theseresources. In one example, these resources may include applicationsoftware licenses. Security provides identity verification for cloudconsumers and tasks, as well as protection for data and other resources.User portal 2083 provides access to the cloud computing environment forconsumers and system administrators. Service level management 2084provides cloud computing resource allocation and management such thatrequired service levels are met. Service Level Agreement (SLA) planningand fulfillment 2085 provide pre-arrangement for, and procurement of,cloud computing resources for which a future requirement is anticipatedin accordance with an SLA.

Workloads layer 2090 provides examples of functionality for which thecloud computing environment may be utilized. Examples of workloads andfunctions which may be provided from this layer include: mapping andnavigation 2091; software development and lifecycle management 2092;virtual classroom education delivery 2093; data analytics processing2094; transaction processing 2095; and storing and verifying changesmade to as-captured sensor device media data 2096.

The descriptions of the various embodiments of the present inventionhave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Likewise,examples of features or functionality of the embodiments of thedisclosure described herein, whether used in the description of aparticular embodiment, or listed as examples, are not intended to limitthe embodiments of the disclosure described herein, or limit thedisclosure to the examples described herein. Many modifications andvariations will be apparent to those of ordinary skill in the artwithout departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to best explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

What is claimed is:
 1. A computer-implemented method comprising:receiving, by a computer, a capture device output, the outputrepresenting an aspect of a recorded event; cryptographicallyprocessing, by the computer, the capture device output to produce avalidatable master file, the master file including at least one primarysubset; wherein the validatable master file includes a master file mediadata primary subset from the capture device output, master metadata, andmaster file blocktree data; and wherein the master file blocktree dataincludes a master file block history portion, a master file signaturekey portion, and a signed hash of the master file media data primarysubset.
 2. The computer-implemented method of claim 1, wherein thecryptographic processing includes: dividing the media data, by thecomputer, into at least one tracked data subset corresponding to theprimary subset; generating, by the computer, a hash of the at least onetracked data subset; generating, by the computer, metadata of the hashof the at least one tracked data subset; combining, by the computer, thehash and the metadata of the hash into at least one tracked data packet;and cryptographically signing, by the computer, the at least one datapacket.
 3. The computer-implemented method of claim 1, furtherincluding: modifying, by the computer, the master file media dataprimary subset to produce a reference file media data primary subset;preparing, by the computer, a reference file including the referencefile media data primary subset, reference file metadata, and referencefile blocktree data; wherein the reference file blocktree data includesthe master file blocktree data and blocktree incrementing information,wherein the blocktree incrementing information includes a hash of themaster file blocktree data, reference file blocktree metadata, a signedhash of primary subset metadata, a signed hash of a change logincrementing the media data primary subset from the master file mediadata primary subset, and a signed hash of the reference file media dataprimary subset.
 4. The computer-implemented method of claim 3, whereinthe reference file further includes instructions indicating replicablechanges made, by the computer, between the modified primary subset mediaand the master file media data primary subset.
 5. Thecomputer-implemented method of claim 1, further including: receiving, bythe computer, a challenged master file identified as a copy of thevalidatable master file; receiving, by the computer, a request tovalidate the challenged master file; and executing, by the computer, amaster file validation routine to assess validity of the challengedmaster file; wherein the master file validation routine includeshashing, by the computer, media data primary subset of the challengedmaster file to generate a hashed challenged master file media dataprimary subset; unsigning, by the computer, a signed hash portion of themedia data primary subset of the challenged master file to generate anunsigned challenged master file media data primary subset; anddetermining, by the computer, whether the hashed challenged master filemedia data primary subset and the unsigned challenged master file mediadata primary subset match.
 6. The computer-implemented method of claim3, further comprising: receiving, by the computer, a reference fileidentified as a modified version of the master file; receiving, by thecomputer, a request to determine whether the reference file is amodified version of the master file; and executing, by the computer, areference file verification routine; wherein the reference fileverification routine includes determining, by the computer, whether thehash of the master file blocktree data and a hash of blocktree data ofthe reference file match; and applying, by the computer, changesindicated by the blocktree incrementing information to a media dataprimary subset in the reference file to generate a hashed reference filemedia data primary subset and unsigning reference file blocktree data togenerate unsigned reference file blocktree data; and determining, by thecomputer, whether the hashed reference file media data primary subsetand the unsigned reference file blocktree data match.
 7. Thecomputer-implemented method of claim 6, further comprising: receiving,by the computer, a reference file identified as an authenticmodification of the master file; receiving, by the computer, adistributable file; receiving, by the computer, a request to determinewhether the distributable file is an authentic modification of thereference file identified as an authentic modification of the masterfile; and executing, by the computer, a distributable file verificationroutine; wherein the distributable file verification routine includesdetermining whether a hash of distributable file blocktree data matchesa hash of the reference file blocktree data and whether a hash of adistributable file media data primary subset matches a correspondingunsigned hash of a representative media block.
 8. A system whichcomprises: a computer system comprising a computer readable storagemedium having program instructions embodied therewith, the programinstructions executable by a computer to cause the computer to: receivea capture device output, the output representing an aspect of a recordedevent; cryptographically process, the capture device output to produce avalidatable master file, the master file including at least one primarysubset; wherein the validatable master file includes a master file mediadata primary subset from the capture device output, master metadata, andmaster file blocktree data; and wherein the master file blocktree dataincludes a master file block history portion, a master file signaturekey portion, and a signed hash of the master file media data primarysubset.
 9. The system of claim 8, wherein the instructions tocryptographically process further cause the computer to: divide themedia data into at least one tracked data subset corresponding to theprimary subset; generate a hash of the at least one tracked data subset;generate metadata of the hash of the at least one tracked data subset;combine the hash and the metadata of the hash into at least one trackeddata packet; and cryptographically sign the at least one data packet.10. The system of claim 8, further including instructions causing thecomputer to: modify the master file media data primary subset to producea reference file media data primary subset; prepare a reference fileincluding the reference file media data primary subset, reference filemetadata, and reference file blocktree data; wherein the reference fileblocktree data includes the master file blocktree data and blocktreeincrementing information, wherein the blocktree incrementing informationincludes a hash of the master file blocktree data, reference fileblocktree metadata, a signed hash of primary subset metadata, a signedhash of a change log incrementing the media data primary subset from themaster file media data primary subset, and a signed hash of thereference file media data primary subset.
 11. The system of claim 10,wherein the reference file further includes instructions indicatingreplicable changes made, by the computer, between the modified primarysubset media and the master file media data primary subset.
 12. Thesystem of claim 8, further including instructions causing the computerto: receive a challenged master file identified as a copy of thevalidatable master file; receive a request to validate the challengedmaster file; and execute a master file validation routine to assessvalidity of the challenged master file; wherein the instructions masterfile validation routine includes directions further causing the computerto hash media data primary subset of the challenged master file togenerate a hashed challenged master file media data primary subset;unsign a signed hash portion of the media data primary subset of thechallenged master file to generate an unsigned challenged master filemedia data primary subset; and determine whether the hashed challengedmaster file media data primary subset and the unsigned challenged masterfile media data primary subset match.
 13. The system of claim 10,further comprising instructions causing the computer to: receive areference file identified as a modified version of the master file;receive a request to determine whether the reference file is a modifiedversion of the master file; and execute a reference file verificationroutine; wherein the reference file verification routine includesinstructions further causing the computer to determine whether the hashof the master file blocktree data and a hash of blocktree data of thereference file match; and apply changes indicated by the blocktreeincrementing information to a media data primary subset in the referencefile to generate a hashed reference file media data primary subset andunsigning reference file blocktree data to generate unsigned referencefile blocktree data; and determine whether the hashed reference filemedia data primary subset and the unsigned reference file blocktree datamatch.
 14. The system of claim 13, further comprising instructionsfurther causing the computer to: receive a reference file identified asan authentic modification of the master file; receive a distributablefile; receive a request to determine whether the distributable file isan authentic modification of the reference file identified as anauthentic modification of the master file; and execute a distributablefile verification routine; wherein the distributable file verificationroutine includes instructions causing the computer to determine whethera hash of distributable file blocktree data matches a hash of thereference file blocktree data and whether a hash of a distributable filemedia data primary subset matches a corresponding unsigned hash of arepresentative media block.
 15. A computer program product comprising acomputer readable storage medium having program instructions embodiedtherewith, the program instructions executable by a computer to causethe computer to: receive, using the computer, a capture device output,the output representing an aspect of a recorded event; cryptographicallyprocess, using the computer, the capture device output to produce avalidatable master file, the master file including at least one primarysubset; wherein the validatable master file includes a master file mediadata primary subset from the capture device output, master metadata, andmaster file blocktree data; and wherein the master file blocktree dataincludes a master file block history portion, a master file signaturekey portion, and a signed hash of the master file media data primarysubset.
 16. The computer program product of claim 15, wherein theinstructions to cryptographically process further cause the computer to:divide, using the computer, the media data into at least one trackeddata subset corresponding to the primary subset; generate, using thecomputer, a hash of the at least one tracked data subset; generate,using the computer, metadata of the hash of the at least one trackeddata subset; combine, using the computer, the hash and the metadata ofthe hash into at least one tracked data packet; and cryptographicallysign, using the computer, the at least one data packet.
 17. The computerprogram product of claim 15, further including instructions causing thecomputer to: modify, using the computer, the master file media dataprimary subset to produce a reference file media data primary subset;prepare, using the computer, a reference file including the referencefile media data primary subset, reference file metadata, and referencefile blocktree data; wherein the reference file blocktree data includesthe master file blocktree data and blocktree incrementing information,wherein the blocktree incrementing information includes a hash of themaster file blocktree data, reference file blocktree metadata, a signedhash of primary subset metadata, a signed hash of a change logincrementing the media data primary subset from the master file mediadata primary subset, and a signed hash of the reference file media dataprimary subset.
 18. The computer program product of claim 15, furtherincluding instructions causing the computer to: receive, using thecomputer, a challenged master file identified as a copy of thevalidatable master file; receive, using the computer, a request tovalidate the challenged master file; and execute, using the computer, amaster file validation routine to assess validity of the challengedmaster file; wherein the instructions master file validation routineincludes directions further causing the computer to hash, using thecomputer, media data primary subset of the challenged master file togenerate a hashed challenged master file media data primary subset;unsign, using the computer, a signed hash portion of the media dataprimary subset of the challenged master file to generate an unsignedchallenged master file media data primary subset; and determine, usingthe computer, whether the hashed challenged master file media dataprimary subset and the unsigned challenged master file media dataprimary subset match.
 19. The computer program product of claim 17,further comprising instructions causing the computer to: receive, usingthe computer, a reference file identified as a modified version of themaster file; receive, using the computer, a request to determine whetherthe reference file is a modified version of the master file; andexecute, using the computer, a reference file verification routine;wherein the reference file verification routine includes instructionsfurther causing the computer to determine, using the computer, whetherthe hash of the master file blocktree data and a hash of blocktree dataof the reference file match; and apply, using the computer, changesindicated by the blocktree incrementing information to a media dataprimary subset in the reference file to generate a hashed reference filemedia data primary subset and unsign, using the computer, reference fileblocktree data to generate unsigned reference file blocktree data; anddetermine, using the computer, whether the hashed reference file mediadata primary subset and the unsigned reference file blocktree datamatch.
 20. The computer program product of claim 19, further comprisinginstructions further causing the computer: receive, using the computer,a reference file identified as an authentic modification of the masterfile; receive, using the computer, a distributable file; receive, usingthe computer, a request to determine whether the distributable file isan authentic modification of the reference file identified as anauthentic modification of the master file; and executing, using thecomputer, a distributable file verification routine; wherein thedistributable file verification routine includes instructions causingthe computer to determine whether a hash of distributable file blocktreedata matches a hash of the reference file blocktree data and whether ahash of a distributable file media data primary subset matches acorresponding unsigned hash of a representative media block.